The efficient operation of test benches within the framework of research and development projects directly correlates with the "health" of the examinee to be investigated. The use of so-called Early Damage Detection Systems (EDDS) is becoming increasingly popular for reasons of Unit Under Test (UUT) monitoring. In the context of this publication the expectations of an EDDS and its structure are discussed as well as its advantages and disadvantages in test bench operation analyzed and compared with the results of measurements. The used EDDS should primarily prevent the damage, up to the loss of the test object by a total loss, in order to ensure a finding possibility of the damaged part at the examined test object. A deviation of the test object behavior from the undamaged condition must be recognized in an early status and must lead to a shutdown of the test bench operation after reaching a defined limit value. With the sensors mounted on the test object it must be able to isolate the cause of the damage in the event of damage detection. For this it is necessary that the EDDS learns in predefined limits within a very short time and is easy to operate for the user. It will be shown that shutdowns of the test bench initiated by the EDDS, are an effectiveness prevention before damage for the UUT. This has been analyzed in the course of various projects. Avoiding major damage on examinees and the resulting reduced additional costs increase the efficiency of the test bench operation. The combination of EDDS with conventional methods for damage prevention, such as the automated compliance with test-relevant limits, regular analyzes of the lubricants and coolants helps to be able to examine the test object ideal. Using an EDDS for efficient test bench operation is therefore essential.